Yazar "Ozgur, Aykut" seçeneğine göre listele

Listeleniyor 1 - 5 / 5
  • Küçük Resim Yok
    Öğe
    In vitro and in vivo evaluation of radiolabeled photosensitizer (Tc-99m-Pheophorbide-a) linked bovine serum albumin nanoparticles for tumor imaging
    (Wiley-Blackwell, 2011) Ozgur, Aykut; Lambrecht, Fatma Y.; Ocakoglu, Kasim; Gunduz, Cumhur; Yucebas, Musteyde
  • Küçük Resim Yok
    Öğe
    In vitro evaluation of apoptosis with Tc-99m-glucoheptonate
    (Pergamon-Elsevier Science Ltd, 2011) Kocagozoglu, Gamze; Lambrecht, Fatma Yurt; Gunduz, Cumhur; Yucebas, Musteyde; Tabar, Elif Bayrak; Ozgur, Aykut; Balci, Tugce
    Radiopharmaceuticals are useful to evaluate effectiveness of cancer treatments as well as diagnosis of diseases. Tc-99m-Glucoheptonate has high sensitivity for imaging lung cancer tissues. In this study, the potential use of Tc-99m-glucoheptonate for monitoring apoptosis related to chemotherapeutic agents is investigated in vitro using A549 lung cancer cell line. A decrease in Tc-99m-glucoheptonate uptake ratio was observed depending on the level of apoptosis. Tc-99m-glucoheptonate is found to be useful for the detection of apoptosis following treatment in A549 lung tumor cells. (C) 2011 Elsevier Ltd. All rights reserved.
  • Küçük Resim Yok
    Öğe
    In vitro evaluation of Tc-99m- EDDA/tricine-HYNIC-Q-Litorin in gastrin-releasing peptide receptor positive tumor cell lines
    (Taylor & Francis Ltd, 2013) Lambrecht, Fatma Yurt; Durkan, Kubra; Ozgur, Aykut; Gunduz, Cumhur; Avci, Cigir Biray; Susluer, Sunde Yilmaz
    Bombesin and its derivatives exhibit a high affinity for gastrin-releasing peptide receptor (GRPr), which is over-expressed in a variety of human cancers (prostate, pancreatic, lung, etc.). The aim of this study was to investigate the in vitro potential of the hydrazinonicotinamide (HYNIC)-Q-Litorin. Tc-99m labeling was performed by using different co-ligands: tricine and ethylenediamine diacetic acid (EDDA). The radiochemical stability of radiolabeled peptide conjugates was checked at room temperature and in cysteine solution up to 24 h. The in vitro cell uptake of Tc-99m-EDDA-HYNIC-Q-Litorin and Tc-99m-tricine-HYNIC-Q-Litorin were evaluated on pancreatic tumor and control cell lines. Optimum specific activity and incubation time were determined for all the cell lines. The results showed that the cell uptake of the radiolabeled peptide conjugates in tumor cell lines were higher than in the control cell line. The findings of this study indicated the need for further development of in vivo study as a radiopharmaceutical for pancreatic tumor imaging.
  • Küçük Resim Yok
    Öğe
    Synthesis and biological evaluation of radiolabeled photosensitizer linked bovine serum albumin nanoparticles as a tumor imaging agent
    (Elsevier Science Bv, 2012) Ozgur, Aykut; Lambrecht, Fatma Yurt; Ocakoglu, Kasim; Gunduz, Cumhur; Yucebas, Musteyde
    In this study, we reported on the synthesis and biological evaluation of radiolabeled fluorescent dye conjugated bovine serum albumin nanoparticles within the size range 190-210 nm. The bovine serum albumin nanoparticles (BSANPs) were prepared using a desolvation method, and chemical cross-linking was performed using gluteraldehyde. Furthermore, pheophorbide-a (PH-A) was loaded on the BSANPs. The results obtained from dynamic light scattering and electron microscopy have proved that nanoparticles are highly monodisperse and near-spherical shaped. The photo-physical properties of the PH-A-BSANPs were obtained using the spectrophotometric techniques. According to the results, PH-A and BSANPs show high non-covalent interaction. PH-A loaded nanoparticles were labeled with Tc-99m and the radio-labeling efficiency was determined as 90 +/- 1.2%. Biodistribution studies of Tc-99m labeled PH-A-BSANPs and PH-A were carried out using female Albino Wistar rats, and Tc-99m-PH-A-BSANPs showed a significantly higher uptake in the breast and uterus than Tc-99m-PH-A. Cell culture study was carried out in MCF-7 cell line ( human breast adenocarcinoma cell line). According to the cell culture studies, Tc-99m-PH-A-BSANPs showed a higher uptake than Tc-99m-PH-A. Moreover, PH-A-BSANPs demonstrated good photo-physical properties and BSANPs increased the uptake of PH-A on to the MCF-7 cell line. These results confirm that Tc-99m labeled PH-A-BSANPs could be utilized for radioimaging. (C) 2011 Elsevier B. V. All rights reserved.
  • Küçük Resim Yok
    Öğe
    Synthesis and biological evaluation of receptor-based tumor imaging agent: Tc-99m-folate-glucaric acid
    (Elsevier Science Bv, 2011) Onursal, Mehmet; Lambrecht, Fatma Yurt; Ozgur, Aykut
    The aim of the present study was to prepare Tc-99m-folate-glucaric acid and investigate the radiopharmaceutical potential for tumors imaging that over express folate receptor. Folate-glucaric acid was synthesized and the synthesized folate conjugate was confirmed with H-1 NMR and LC-MS/MS methods. Folate-glucaric acid was labeled with Tc-99m, and its radiolabelling efficiency was found as 96 +/- 2.0%. Biodistribution study of Tc-99m-folate-glucaric acid was carried out in vivo using two groups of female Albino Wistar rats: folate receptor (FR) saturated and unsaturated. Biodistribution study showed that Tc-99m-folate-glucaric acid indicated high uptake in folate receptor rich tissues such as breast, ovary and uterus. Therefore, Tc-99m-folate-glucaric acid shows good radiolabeling and biodistribution in FR organs, the radiolabeled conjugate is a reason potentially useful radiopharmaceutical for detection of FR-positive tumors. (C) 2011 Elsevier B.V. All rights reserved.